Drilling rate recorder



Jan. 23, 1962 w. s. GREEN DRILLING RATE RECORDER 3 Sheets-Sheet 1 Filed June 26, 1957 WILLIAM G. GREEN Fig.ll

Jan. 23, 1962 w. G. GREEN DRILLING RATE RECORDER 3 Sheets-Sheet 2 Filed June 26, 1957 INVENTOR.

WILLIAM G. GREEN Jan. 23, 1962 w. ca. GREEN 3,017,770

DRILLING RATE RECORDER Filed June 26, 1957 5 Sheets-Sheet 3 \J m l a/E] 2 3 m i m a g 1 I a: i In t 2 j E I 8 0 N h g g N 'n r o O 0 U U L INVENTOR.

' WILLIAM G. GREEN 3,017,770 DRILLING RATE RECORDER William G. Green, Tulsa, Okla. (3210 46th Ave. N., St. Petersburg, Fla.) Filed June 26, 1957, Ser. No. 668,233 3 Claims. (Cl. 73-1515) This invention relates to apparatus for recording the rate of drilling of oil wells. More particularly the invention is directed to an improved drilling rate recorder which will accurately chart the rate of penetration of a drill with reference to the depth of the bore so that changes in drilling rate, such as occur when the drill bit passes from a relatively hard subsurface formation to a porous formation of the type likely to bear oil, will be readily ascertained.

It is a principal object of the present invention to provide an improved drilling rate recorder of the above mentioned character comprising a chart which is moved only in proportion to downward progress of the drill, and includes a mechanism for marking the chart upon successive increments of movement, with a mark indicative of the time expended during each increment, whereby a succession of such marks provides a graphic presentation of the instantaneous drilling rate at each increment of well depth.

Another object of this invention is the provision of a well drilling recorder wherein the chart marking mechanism includes a lead screw extending transverse to chart movement and rotated at a constant rate, a stylus operating means having a stylus carrying member which is brought into releasable engagement with the lead screw to move the stylus at a constant rate from an initial position and until the drill has advanced a predetermined distance, at which time the stylus carrying member is released from the lead screw and the stylus is brought into marking engagement with the chart and returned to its initial position for repeated movement by the lead screw.

Other objects and advantages of the present invention will become apparent from the following description of drilling rate recording apparatus embodying the invention, and from the accompanying sheets of drawings forming a part of this specification and in which:

FIG. 1 is a somewhat schematic illustration of oil well drilling apparatus including a drilling rate recorder embodying the invention;

FIG. 2 is a front elevation of the drilling rate recorder of FIG. 1;

FIG. 3 is a top plan view of the recorder;

FIG. 4 is a schematic view illustrating the relationship of components of the recorder;

FIG. 5 is an enlarged elevational view of a measuring wheel forming part of the recorder;

FIG. 6 is a sectional view of the wheel of FIG. 5;

FIG. 7 is a schematic view showing the form of chart strip drive utilized in the recorder;

FIG. 8 is a fragmentary view of a stylus operating means;

FIG. 9 is an enlarged view of a governor operated switch mechanism forming part of the apparatus of FIG. 1;

FIG. 10 is a schematic illustration of electrical circuitry for the recorder; and

FIG. 11 is a view similar to FIG. 8 and illustrating a modified form of stylus operating means.

Referring to FIG. 1, there is illustrated therein a well drilling apparatus including a derrick structure 10 from which is supported a string of drill pipe 12 having a drill bit 12a shown in a partially completed bore 13. Pipe 12 is supported from the upper portion of the derrick by block and tackle means including conventional swivel 14, traveling block 17, fixed block means 18 at the top of the 3,017,770 Patented Jan. 23, 1962 derrick, and a cable 20 leading from a draw works drum 21, through the stationary and movable blocks, and terminating in a deadline portion 20a which is anchored as at 22. Each block includes the necessary sheaves to receive the number of lines of cable necessary to provide the mechanical advantage desired in this block and tackle system, and drum 21 reels in and pays out cable 20 to raise and lower traveling block 17, swivel joint 14, and the entire length of drill pipe 12 as required from time to time in drilling operations.

Drill pipe 12 extends through a rotary table 24 which is driven by suitable pinion means 25 to provide rotary motion to the pipe, and drill bit 12a thereof, to perform the drilling in a manner well known in the art to which the invention pertains.

A drilling rate recorder, generally indicated at 30 in FIG. 1, has a measuring wheel 31 which is adapted to be rotated in accordance with vertical movements of drill pipe 12 by means of a wire line 33 which is connected to swivel 14 and leads around a sheave 34 forming part of block 18, around measuring Wheel 31, and onto a spring retracted spooling device 35. Spooling device 35 maintains line 33 taut at all times, but permits movement thereof in either direction as swivel 14 and pipe string 12 moves up or down, whereby measuring wheel 31 is rotated in accordance with movement of the pipe string. Drilling rate recorder 30, described more fully hereinafter, is adapted to provide a graphic presentation of the rate of downward drilling progress of drill pipe 12, and which presentation accurately shows the rate of drilling which occurred at each foot of drilling progress or fractions thereof.

Referring now to FIGS. 2 and 3, the drilling rate recorder includes a frame 36 which houses or supports the components of the recorder including measuring wheel 31, approximately one-half of which is exposed for engagement with wire line 33. FIG. 4 provides a somewhat schematic illustration of the relationships of the components of the recorder, the details of which will be discussed with reference to accompanying views.

It will be seen from FIGS. 4-6 that measuring wheel 31 is rotatably mounted by bearing means 3101 on a shaft 37 which is suitably journalled in an opening 36a in frame 36. Measuring wheel 31, which is rotated by movements of wire line 33, is adapted to impart rotary movement in one direction to shaft 37 through a ratchet wheel 38 fixed to the shaft, and a pawl 39 which is pivoted to wheel 31 by pivot pin 40 and has a tip 3911 which is in engagement with the teeth 38a of the ratchet wheel. Pawl 39 is resiliently biased into engagement with the teeth of ratchet wheel 38 by a compression spring 41 acting between the pawl and the frame of an electromagnet 42. A stop member 43 limits movement of pawl 39 in a direction away from electromagnet 42 so that rotation of wheel 31 in a clockwise directon as indicated by arrow A in FIG. 5 will impart rotation to shaft 37, while upon rotation of wheel 31 in a counter-clockwise direction as indicated by arrow B, spring 41 will allow pawl 39 to act as a ratchet and rotation of the measuring wheel will be independent of shaft 37. A gear 44 is fixed t0 shaft 37 for rotation therewith and is in driving engagement with a gear 45 fixed to a shaft 46 carrying a rubber covered roller 47 for advancing a chart strip 48 in accordance with downward progress of the drill pipe 12. Chart 48 is held against roller 47 by a rubber covered, spring biased idler roller 47a, and is advanced from an initially filled magazine 49a to an initially empty magazine 4%, as shown in FIG. 7. The gears 44 and 45 are preferably chosen to elfect advancement of chart strip 48 at such a rate that indicia 48a thereon correspond to feet of well depth.

Inasmuch as wheel 31 is adapted to drive shaft 37 through ratchet pawl 39 in one direction only, this being in a direction corresponding with downward travel of pipe 12, upward movement of pipe 12, such as is required at times, will have no effect on chart strip 48. In addition, energization of coil 42a of electromagnet 42 serves to withdraw pawl 39 from engagement with ratchet wheel 38 so that wheel 31 may rotate in either direction with respect to shaft 37 to permit drill pipe 12 to be lowered in bore 13 to a drilling position Without advancing the recording strip 48. Energization of winding 42a of electromagnet 42 to permit free-wheeling movement of wheel 31 may be effected automatically by circuit means including a governor operated switch means 54 which is closed whenever rotation of table 24 is below a predetermined speed, or by a switch means generally indicated at 55 which is actuated by tension experienced in deadline portion 28a of cable 20 upon hoisting of the drill pipe 12,

Switch means 54, best shown in FIG. 9, comprises a governor mechanism 54:: mounted on drive pinion 25, and connected by suitable linkage 54b to normally closed contact means 54c. Since rotation above the mentioned predetermined speed is normally effected only when actually drilling, the switch means 54 serves to prevent operation of the recorder at other times. Switch means 55, best shown in FIG. 1, includes a frame 55a having legs 55b through which deadline portion 28a of cable 20 extends. A plun er 55c engages a bight of deadline 20a between legs 55]) and is adapted to be moved by straightening of the bight to close normally open switch mechanism 55d. Since the bight straightens when cable 20 is tensioned upon hoisting the drill pipe string, operation of the recorder is prevented at such times.

Referring now to FIG. 10, it will be recognized that closing of either or both of the switch means 54 and 55 will complete a circuit including one or both of these switches, a conductor 57, a battery or other power source 58, a conductor 59, a manually operable switch 68, and the solenoid of a normally open relay o1. Energization of relay 61 closes contacts 62 thereof, completing a circuit including a conductor 63, winding 42a of pawl actuating magnet 42, conductor 57, battery 58 and switch 60. Thus, the switches 54 and 55 serve to automatically disengage wheel 31 from shaft 37 to prevent advancement of recording strip 48 at times other than when drilling is actually in progress.

Referring again to the schematic illustration of FIG. 4, the drilling rate recorder 38 includes a chart marking mechanism generally indicated at 70 for scribing a line or series of lines 71 on chart strip 48 at equal increments of chart travel, for example corresponding to tenths of a foot of progress of pipe 12, with the length of each line 71 corresponding to the amount of drilling time required for each increment. Remembering that movement of chart strip 48 corresponds to progress of drilling pipe 12, it will be recognized that an increase in the length of lines 71, such as is shown at 71a, represents a proportional decrease in rate of drilling progress, while decreasing line lengths, as indicated at 71b, indicates an increased rate of drilling progress.

The mechanism 70 for inscribing lines 71 comprises a lead screw 73 which extends transverse to the direction of travel of chart strip 48 and is rotated at a constant rate by a suitable clock type synchronous motor 74 connected to lead screw 73 by gears 75 and 76 and energized by a suitable alternating current source 77. A stylus operating mechanism 80 is adapted to be moved by lead screw 73 from right to left (as viewed in FIG. 4) across chart strip 48 at a constant rate and during which movement a stylus 81 is held off of chart strip 48 by the stylus operating mechanism. As is best shown in FIG. 8, stylus operating mechanism 88 comprises a core structure including end plates 82, a solenoid coil 83 between end plates 82, and a pair of supporting brackets 84 extending outwardly from the end plates, with the brackets, plates, and coil all secured together by a through bolt 85. Brackets 84 are attached to a U-shaped, brass traveling block 87 having holes 87a through which parallel guide rods 88 extend and support the mechanism for transverse movement across chart strip 48 by lead screw 73.

Motion is transmitted from lead screw 73 to stylus operating mechanism 80 through a movable half-nut 90 which has threads 99a facing the lead screw and is carried on a. ferric plate 91 from which stylus 81 extends. Plate 21 has a set of holes 92 receiving screws 93 which are threaded into and extend downward from a pair of brass blocks 94 attached to core plates 82. Screws 93 serve to guide plate 91 in movement toward and away from core plates 82. A compression spring 95 surrounds each of the screws 93 and serves to bias plate 91, halfnut 98, and stylus 81 away from lead screw 73. Plate 91 and half-nut 98 comprise armature means, and when coil 83 is energized plate 91 is attracted to core plates 82 overcoming the bias of springs 95 and causing halfnut 98 to threadedly engage lead screw 73 so that the stylus operating mechanism is moved at a constant rate thereby while holding stylus 81 out of engagement with chart strip 48. Upon de-energization of coil 83 halfnut 90 moves out of engagement with lead screw 73, permitting stylus 81 to come in contact with chart strip 48, and also releasing the stylus operating mechanism for rapid movement from left to right by a tension spring 97, and during which movement stylus 81 inscribes a line 71 on the chart strip. Of course, when mounted in the position illustrated, stylus 81 and plate 93 tend to move downwardly by their own weight.

Energization of coil 83 is controlled by a switch 99 having a spring loaded plunger 100 and a cam follower 181 which rides the periphery of a cam 102 which is mounted for rotation with shaft 37. Switch 99 is held closed by earn 102 during the major portion of the rotation of shaft 37 corresponding to drilling progress, and completes a circuit from a power supply such as battery 104, through a conductor 105, solenoid coil 83, conductor 106, switch 39, and conductor 107 to battery 104. Although this circuit is maintained during the major portion of the rotation of cam 102, it is momentarily interrupted when cam follower 101 engages a notch 103 on the cam. Such momentary interruption of this circuit permits scribe operating mechanism 80 to be released from lead screw 73 and rapidly returned to its initial right hand position so as to cause a line 71 to be inscribed on the chart strip in the manner previously described.

The stylus 81 may be of brass or lead, and the chart strip, which may be carbon or other special paper, is preferably backed by a suitabl plate 110. By providing transverse graduations 48b, either on chart 48 or on a superimposed rule, the drilling rates can be quickly measured. It is changes in drilling rate, however, that are of particular interest to the operators and the series of lines 71 of varying lengths provide that information directly.

A presentation of instantaneous drilling rate is provided by an electrical drilling rate meter, the circuit of which is indicated generally at in FIG. 10. Shaft 46, which turns in direct proportion to the downward movement of drill pipe 12, is shown in FIG. 4 to be equipped with a sprocket-type cam 121 which moves a cam follower 122a of a miniature switch 122 so as to alternately open and close that switch, Switch 122 forms part of circuit 120 and the frequency of opening and closing thereof is indicated by the reading of a microammeter 123, also forming part of that circuit and which may be calibrated directly in inches of drilling progress per minute.

Momentary closing of switch 122 sends an impulse of current through normally closed contacts 124, 125 of a relay 126. A portion of this current passes through resistors 128, 129, 130, switch 131 and micro-ammeter 123 causing deflection of the needle thereof. Another portion of the current serves, at the same time, to charge condensers 132 and 133. Still another portion of the current charges a condenser 134 connected across leads 135 and 136 of relay 126. The rate of charging of condenser 134 is determined in part by resistor 137 and, after a predetermined charging time relay 126 will be actuated opening contacts 124, 125 and closing contacts 124, 138. Condensers 132 and 133 will then discharge through micro-ammeter 123 tending to maintain the deflection thereof when contacts 124, 125 are open. After switch 122 is permitted to open by cam 121, the charge in condenser 134 will have dissipated through relay 126 allowing it to close contacts 124, 125 in readiness for the next pulse.

Because of the smoothing action of condensers 132, 133 and resistors 128, 129 and 130, the deflection of micro-ammeter 123 will represent an averaging of the current flows. Changes in frequency of closing of switch 122 will be reflected by corresponding changes in meter deflection, thereby providing a direct indication of rate of drilling progress. Switch 131 is provided to short out a resistor 140 only during the charging phase of condensers 132, 133, thereby providing a more steady deflection of micro-ammeter 123 when these condensers discharge.

Referring now to FIG. 11, the modified stylus operating mechanism 145 comprises two half-nut members 146, 147 carried in spaced, magnet frame sections 148 and 149 respectively. Opposite end portions of frame sections 148, 149 are surrounded by solenoid windings 150, 151 which, when energized draw the frame sections together causing half-nuts 146, 147 to engage the lead screw 173. A stylus 152 is mounted on frame section 149 and springs 154 normally bias the frame sections apart to permit return by spring 97 and marking of the chart strip by the stylus.

The drilling rate recorder 30 of this invention may be used to advantage in conjunction with data determining devices such as the mud weight and viscosity determining apparatus as shown and described in my copending application S.N. 652,053, filed April 10, 1957, and now abandoned. Thus, a suitable connection may be made between shaft 43 of recorder 30 and the recorder drive shaft 157 of the copending application device to provide means for automatically indicating the drilling mud weight and viscosity occurring at a particular depth during a drilling operation.

Although the present invention has been described with detailed reference to a specific drilling rate recorder embodying the invention, it will be understood that the invention is not limited thereto, but rather the invention includes all those modifications, adaptations, and uses as are reasonably embraced by the claims hereof.

From the foregoing description it will be readily seen that there has been produced a device which substantially fulfills the objects of the invention as set forth herein. The invention is not limited to the exemplary constructions herein shown and described, but may be made in many ways within the scope of the appended claims.

Having described my invention, I claim:

1. A drilling rate recorder of the character described comprising a frame, chart drive means mounted in said frame for advancing a chart strip in one direction at a rate proportional to downward movement of a well drilling member, a lead screw extending transverse to said one direction, means for rotating said lead screw at a constant speed, stylus operating means supporting a stylus and engageable with said lead screw for moving said stylus at a constant rate from an initial position across said chart strip while holding said stylus out of marking engagement therewith, said stylus operating means being releasable from said lead screw for return movement of said stylus across said chart to said initial position while holding said stylus in marking engagement with said chart strip, spring means acting between said frame and stylus operating means for effecting said return movement, and control means connected between said chart drive means and said stylus operating means so as to eifect momentary release of the latter from said lead screw upon predetermined increments of chart advancement.

2. A drilling rate recorder as defined in claim 1 wherein said stylus operating means comprises solenoid means and armature means, said armature means including a half-nut member movable into and out of engagement with said lead screw upon energization and deenergization respectively of said solenoid, and wherein said stylus is connected with said half-nut member for movement out of and into engagement with said chart strip upon said energization and deenergization respectively.

3. A drilling rate recorder as defined in claim 1 and wherein said stylus operating means comprises electromagnet means, .and half-nut means operated by said electromagnet means upon energization and deenergization thereof to move into and out of engagement withsaid lead screw, said stylus being mounted for movement with said half-nut means, and wherein said control means comprises a cam rotated by said chart drive means and a switch means operated by said cam to effect said energization and deenergization of said electromagnet means.

References Cited in the file of this patent UNITED STATES PATENTS 2,108,014 Jones Jan. 15, 1937 2,330,752 Sikes Sept. 28, 1943 2,365,014 Silverman et a1. Dec. 12, 1944 2,390,178 Rutherford Dec. 4, 1945 

